電鍍是一種電化學(xué)過程，也是一種氧化還原過程。電鍍的基本過程是將零件浸在金屬鹽的溶液中作為陰極，金屬板作為陽極，接直流電源后，在零件上沉積出所需的鍍層。
Electroplating is not only an electrochemical process, but also a redox process. The basic process of electroplating is to immerse the parts in the solution of metal salt as the cathode and the metal plate as the anode. After connecting with the DC power supply, the required coating is deposited on the parts.
例如：鍍鎳時，陰極為待鍍零件，陽極為純鎳板，在陰陽極分別發(fā)生如下反應(yīng)：
For example, during nickel plating, the cathode is the part to be plated and the anode is pure nickel plate. The following reactions occur at the cathode and anode respectively:
陰極(鍍件)：Ni2++2e→Ni(主反應(yīng))
Cathode: Ni2 + + 2e → Ni (main reaction)
2H++e→H2↑(副反應(yīng))
2H + + e → H2 ↑ (side reaction)
陽極(鎳板)：Ni﹣2e→Ni2+(主反應(yīng))
Anode (nickel plate): ni-2e → Ni2 + (main reaction)
4OH-﹣4e→2H2O+O2+4e(副反應(yīng))
4OH - - 4E → 2H2O + O2 + 4E (side reaction)
不是所有的金屬離子都能從水溶液中沉積出來，如果陰極上氫離子還原為氫的副反應(yīng)占主要地位，則金屬離子難以在陰極上析出。根據(jù)實(shí)驗(yàn)，金屬離子自水溶液中電沉積的可能性，可從元素周期表中得到一定的規(guī)律。
Not all metal ions can be deposited from aqueous solution. If the side reaction of hydrogen ion reduction to hydrogen on the cathode is dominant, it is difficult for metal ions to precipitate on the cathode. According to the experiment, the possibility of electrodeposition of metal ions from aqueous solution can be obtained from the periodic table of elements.
陽極分為可溶性陽極和不溶性陽極，大多數(shù)陽極為與鍍層相對應(yīng)的可溶性陽極，如：鍍鋅為鋅陽極，鍍銀為銀陽極，鍍錫-鉛合金使用錫-鉛合金陽極。但是少數(shù)電鍍由于陽極溶解困難，使用不溶性陽極，如酸性鍍金使用的是多為鉑或鈦陽極。鍍液主鹽離子靠添加配制好的標(biāo)準(zhǔn)含金溶液來補(bǔ)充。鍍鉻陽極使用純鉛，鉛-錫合金，鉛-銻合金等不溶性陽極。
The anode is divided into soluble anode and insoluble anode, most of which are soluble anode corresponding to coating, such as zinc anode for zinc plating, silver anode for silver plating, and tin lead alloy anode for tin lead alloy plating. However, due to the difficulty in anodic dissolution, insoluble anodes are used in a few electroplating processes. For example, platinum or titanium anodes are mostly used in acid gold plating. The main salt ions in the plating bath are supplemented by adding standard gold containing solution. Chromium plating anode uses pure lead, lead tin alloy, lead antimony alloy and other insoluble anode.